Vending machines often include change payout apparatus for paying out change to a customer in the event of an excess deposit, i.e., a deposit which exceeds the vend price. Examples of such vending machines are set forth in U.S. Pat. Nos. 3,754,629, 3,820,642, and 3,841,456, all of which are assigned to the present assignee.
In vending machines capable of paying out change in the event of an excessive customer deposit, a plurality of a coin tubes generally are utilized for storing coins. Each coin tube is designated to store coins of one denomination, e.g., quarter, nickel, or dime. Initially, an operator fills each coin tube with the designated denomination. In operation, when a customer makes an excess deposit, the amount of change due is determined and paid out from the coin tubes.
To avoid having to frequently manually replenish the coin tubes, a deposited coin is supplemented to coins of the same denomination stored in a coin tube if the coin tube is not full. If the coin tube is full, a deposited coin is routed to a cash box. For example, if the quarter tube is not full, deposited quarters will be routed to the quarter tube. If the quarter tube is full, deposited quarters will be routed to the cash box. Examples of vending machines including coin tubes and routing mechanisms are set forth in U.S. Pat. Nos. 3,963,035, 4,587,984, and 5,184,708, all of which are assigned to the present assignee.
Vending machines also typically include structure to sense the number of coins in each coin tube and to control the payout of change using the highest possible denominations of coins. Lower denomination coins are used if the quantity of coins in the higher denomination coin tubes has fallen below a predetermined level. Paying out change using the highest possible denominations of coins generally is known as a "least coin payout". Paying out change using the highest denomination of coins facilitates maintaining a better "mix" of coins stored in the coin tubes and operating a vending machine for longer periods of time without requiring customers to deposit exact change.
Once the quantity of coins in a coin tube falls to a predetermined level, and if payout of proper change is not possible without a coin from such tube, the vending machine requires an exact deposit equal to the vend price to make a sale. A customer, fully aware that proper change is not possible, could still make an excess deposit and a vend operation would be performed. Under such circumstances, however, the customer will receive a payout less than the difference between the vend price and the amount deposited. Examples of such coin level detection and payout control are set forth in U.S. Pat. Nos. 3,963,035 and 4,587,984, which are mentioned above, and U.S. Pat. No. 4,763,769, which is assigned to the present assignee.
Since many customers often do not have coins readily available to make such an exact deposit, sales usually are lost when a vending machine requires exact deposit. Further, having an operator frequently replenish the coin tubes for each vending machine generally is expensive, particularly when a number of vending machines are located in a large geographic area.
Although the least coin payout method is useful and provides many advantages, there exists a need for maintaining even a better mix of coins stored in the coin tubes. For example, one coin denomination may not be paid out as often as other coin denominations, even though such one coin denomination is available and could be used. As a result, the coin tube for the one denomination remains full as other coin tubes are depleted.
Attempts to maintain a better mix of coins stored in the coin tubes include payout systems which generate and evaluate a plurality of alternative payout combinations. Specifically, using alternative payout methodologies, alternative payout combinations or arrays are generated. One payout combination is then selected, based on, for example, which combination is "best", for making the actual payout. A hierarchy of rules may be utilized to determine which combination is "best". An example of such a system is described in PCT Patent Application WO 94/03875, published Feb. 17, 1994. Such systems which generate alternative payout combinations and then select one combination to make the actual payout are complex, certainly as compared to routines which only make a payout using the least coin payout method. The more complex routines are more difficult to implement and are more susceptible to errors. Such routines also require more memory storage, which typically increases the cost of the systems.
Accordingly, it is desirable and advantageous to provide a vending machine capable of paying out change for long periods of time without requiring an operator to manually replenish the coin tubes. It is also desirable and advantageous to provide a change payout routine which is easy to implement, does not require excessive memory, yet controls operations so as to maintain a better mix of coins stored in the coin tubes of a vending machine.
An object of the present invention is to provide a vending machine capable of paying out change for long periods of time without requiring an operator to manually replenish the coin tubes.
Another object of the present invention is to provide a vending machine which provides an accurate payout to a customer and operates to facilitate preventing the quantity of coins for each coin type stored in the machine coin tubes from falling below a predetermined level.
Yet another object of the present invention is to provide a change payout routine which is easy to implement, does not require excessive memory, and controls operations so as to maintain a better mix of coins stored in the coin tubes.